高浓度废水可调式厌氧处理技术

以酒精发酵和有机化工混合废水为研究对象,通过对原厌氧工艺的改进,成功地研发了"可调式Ⅰ级全糟发酵/DDG+Ⅱ级UASB+Ⅲ级IC"厌氧工艺,实现了废水有机负荷和进入方式的随机调节。运行结果表明:新工艺运行稳定,有机负荷提高1倍,沼气产率提高39%~56%,厌氧阶段出水COD由原工艺的2000 mg/L降低到500 mg/L左右,COD去除率由93%上升到99%。     

优质发酵酒精生产酒糟废水回用技术研究

研究以控制优质发酵酒精贸易中二叶恶烷限量为目标,通过实验室模拟研究了不同水源做工艺拌料水时酒精中二叶恶烷含量对比,确定地下水为优质发酵酒精生产的工艺用水;研究了酒糟污水处理后SBR水对酒精发酵质量影响;将小试结论用于酒精生产的实际工艺,产品中二叶恶烷含量检测表明,60%SBR水40%地下水能够满足优质酒精的工艺用水要求。对SBR水反复回用3次后,酒精中二噁烷含量仍处于较低水平,能够满足优质酒精贸易中二叶恶烷限量的要求。     

糟液循环对开放式餐厨垃圾乙醇发酵的影响及工艺改进

在前人研究的基础上对餐厨垃圾乙醇发酵糟液进行多次循环使用,以减少废液的排放量.重点考察了糟液循环对餐厨垃圾产乙醇的影响.结果表明:当未经处理的乙醇糟液在全回流条件下,对乙醇发酵产生明显抑制,全循环4次后乙醇产量由28.4g/L 降至2.56g/L.随着循环利用次数的增加,乳酸、SS、DS和盐分均产生积累,分别达5.45、64.7、99.5和12.3g/L.为提高糟液循环次数,本研究采用2/3的糟液回流和絮凝处理后全回流的方式,其糟液循环利用7次后,前者乙醇产生量维持在25.5~35.5g/L,而后者的乙醇产量在12.2~32.4g/L.糟液2/3回流循环效果要优于絮凝处理后全回流的方式,今后需考虑两者相结合进行糟液循环的方式.     

印染废水处理回用工艺现状研究

印染废水产生量大、有机物含量高、具有一定的毒害性,因此印染废水的回用是降低印染废水污染和印染用水消耗的重要途径,印染废水回用包括原废水和二级生化出水的处理回用。印染废水主要回用于印染生产过程,在以印染原废水处理回用时,典型工艺是生化处理+膜分离组合工艺;在以印染废水处理后的二级生化出水进行处理回用时,其典型工艺分别是超滤+反渗透组合工艺,工艺出水可回用于印染漂洗、染色等生产过程,实现废水厂内循环利用。     

改性聚氨酯海绵的合成及其油水分离性能

以膨胀石墨与氧化锌为原料,采用复合改性法改性聚氨酯海绵,在硅烷偶联剂的作用下,用月桂酸的醇溶液表面修饰后制备出改性聚氨酯海绵. 通过扫描电子显微镜(SEM)与接触角测定仪进行表征,对改性聚氨酯海绵的吸油、吸水及循环使用性能进行了测定,并试验获得了最佳的油水分离条件. 结果表明:改性聚氨酯海绵具有良好的疏水超亲油性,在膨胀石墨分散液与氧化锌胶体溶液体积比为1∶1时,对于质量浓度为20 g/L的机油水溶液,饱和单位吸油量最高可达17.7 g/g,对机油的选择性吸附系数为10.41,油水分离效果最佳;在选择吸附过程中,15 min以内油水分离效率就能达到78.41%;改性聚氨酯海绵每次循环利用后,单位吸油量的减幅均低于7.3%,循环使用性能良好. 研究显示,该种改性聚氨酯海绵对油水体系中的油类具有很好的选择性,吸附完成后,经过简单的挤压将油回收后即可循环利用,具有便捷、高效、循环、无二次污染的特性.      

Reducing water consumption in beet distilleries by recycling the condensates to the fermentation phase

Recycling the stillage condensates produced in beet distilleries into the fermentation phase, would enable both water consumption and wastewater rejection to be reduced. However, it has been demonstrated that at least eight compounds in these condensates caused the inhibition of alcohol production. Their retention by a reverse osmosis (RO) process and preparative chromatography was thus considered. The reverse osmosis treatment led to high rejection coefficients for all neutral compounds whatever the pH, but had to be carried out at basic pH to obtain an almost complete retention of the small acids. Adsorption isotherm measurements carried out on various chromatographic supports showed that acidic compounds were best retained on a weak anionic exchanger and other solutes on a non-polar adsorbent. The coupling of the RO process and chromatography could therefore be a viable alternative for the treatment of these effluents.     

The saccharification–membrane retrieval–hydrolysis (SMRH) process: a novel approach for cleaner production of diosgenin derived from Dioscorea zingiberensis

Diosgenin (CAS number 512-04-9) production from Dioscorea zingiberensis is a very important industry in central-western China. However, treatment of the wastewater with COD up to 50,000 mg/L has been a formidable challenge for the sustainable development of diosgenin industry. A cleaner production process, called the saccharification–membrane retrieval–hydrolysis (SMRH) process, was proposed and pilot-tested by us. The new process combines traditional acid hydrolysis with enzyme hydrolysis and UF/NF technologies. It has two major advantages. (1) The starch in D. zingiberensis is degraded into low molecular weight soluble sugar which is separated and removed before acid hydrolysis of the residue. This prevents the soluble sugar from entering the wastewater; instead it can be utilized as a carbon source in the fermentation industries. (2) UF/NF membrane equipment separates the acid hydrolysis solution into three parts: (a) the colloid phase, (b) the acid solution and (c) the water. All of which can be used in this or in another industry. In this way, the new production process dramatically reduces the wastewater discharge and uses the sugar, acid, water and solid waste in other processes.     

圆红冬孢酵母利用生物柴油副产物粗甘油产油脂的影响因素分析

以餐饮废油制备生物柴油的副产物粗甘油为碳源,采用圆红冬孢酵母发酵生产微生物油脂。通过对发酵影响因素的优化,确定了最适发酵条件为:种子复苏时长24 h、富集时长10 h、接种量为6%、初始粗甘油浓度为60 g/L、C/N为60、有机氮占总氮比例为75%、发酵体积为100 mL、发酵温度为30 ℃、发酵时间为6 d,在此条件下,获得总产油量为10.56 g/L,油脂产率为0.229。与无机氮源硫酸铵相比,有机氮源蛋白胨的添加显著提高了油脂含量和总产油量。通过测定油脂的脂肪酸成分并利用Hoekman方程估算所得生物柴油的性能指标,表明其符合中国、美国及欧盟标准。该方法既为粗甘油的再利用提供了一条新途径,又为生物柴油的生产提供了廉价的原材料。     

制药行业VOCs排放特征及控制对策研究 ——以浙江为例

以浙江省为例,对制药行业VOCs的主要来源和特点进行了分析.采用气相色谱法,对该地区制药行业释放的VOCs作了定性和定量分析,识别出16种VOCs,分别为甲醇、丙酮、苯、甲苯、二甲苯、二氯甲烷、乙酸乙酯、三乙胺、二甲基甲酰胺、醋酸丁酯、正丙醇、乙醇、异丙醇、乙腈、环氧乙烷、甲醛.通过源成分谱图,确定出不同制药类型的主要VOCs污染物.结果表明, 发酵类为丙酮(65%)、乙酸乙酯(30.41%),提取类为丙酮(56.05%)、乙酸乙酯(36.64%)、乙醇(6.97%),化学合成类为异丙醇(44.27%)、丙酮(35.39%)、乙醇(9.78%)、甲苯(3.89%),生物工程类为丙酮(60.99%)、二氯甲烷(14.77%)、乙醇(12%)、甲醛(11.91%).并对上述主要VOCs进行了优先控制排序.最后,结合该行业VOCs的排放特点,提出了制药行业VOCs有效可行的防治对策.     

不同产酸发酵菌群产氢能力的对比与分析

重点对乙醇型发酵菌群和丙酸型发酵菌群的产气及产氢能力进行了对比研究,并对发酵菌群由丙酸型演替为乙醇型过程中的产氢速率变化进行了分析.在有机负荷相同的条件下,乙醇型发酵菌群表现出较高的产氢速率和比产氢速率,最大产氢速率为14.99L/d,最大比产氢速率为3586.45mmol/(kg·d).而丙酸型发酵菌群产氢速率和比产氢速率都较低,分别为3.62L/d,196.46mmol/(kg·d)生物制氢反应器在运行中维持乙醇型发酵更有利于获得较高的氢气产量,应尽量避免丙酸型发酵的发生.     

Remove volatile organic compounds (VOCs) with membrane separation techniques

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｖｏｌａｔｉｌｅｏｒｇａｎｉｃｃｏｍｐｏｕｎｄｓ (ＶＯＣｓ)ｉｓｏｎｅｏｆｔｈｅｆｉｖｅｍａｊｏｒｐｒｉｍａｒｙｇａｓｏｕｓｐｏｌｌｕｔａｎｔｓ(ｐａｒｔｉｃｕｌａｔｅｓ,ＳＯｘ ,ＮＯｘ ,ＶＯＣｓ,ＣＯ) ,ｉｎｗｈｉｃｈ 31ＶＯＣｓｐｏｌｌｕｔａｎｔｓｉｎｃｌｕｄｉｎｇｂｅｎｚｅｎｅ,ａｃｒｏｌｅｉｎａｎｄａｌｉｐｈａｔｉｃ ,ａｒｏｍａｔｉｃｈａｌｏｇｅｎａｔｅｄｈｙｄｒｏｃａｒｂｏｎｓａｒｅｌｉｓｔｅｄｉｎａｌｌ 1 2 9ｐｒｉｏｒｉｔｙｐｏｌｌｕｔａｎｔｓｂｙｔｈｅＥｎｖ…     

Environmentally friendly bagasse pulping with NH4OH–KOH–AQ

Bagasse pulping trials were carried out with NH₄OH–KOH in the presence of anthraquinone for the purpose of reducing or eliminating the black liquor problem in pulping processes. The operating conditions, such as the composition of the cooking liquor, the liquid to bagasse ratio, the maximum cooking temperature and the cooking time at the maximum temperature during the pulping process were investigated systematically to establish optimal pulping conditions. The experimental results indicated that this pulping process is particularly well suited for the pulping of bagasse, where the bagasse was delignified to a low Kappa number value of 11.3, the percentage delignification was 80%, and the pulp yield was 65%. This newly developed pulping process provided a high tensile index of 51.6 N.m/g. The laboratory-scale experimental results were replicated on a pilot-scale process successfully, demonstrating the initial stages of scale-up and also demonstrating a degree of repeatability. There is a good prospect that this process can utilize black liquor, which contains nitrogen, phosphorus, potassium and ammoniacal lignin, as a fertilizer for agricultural production. Hence the black liquor problem associated with the pulping industry can potentially be turned into a benefit through this environmentally friendly bagasse pulping process.     

Development of a life cycle assessment tool for construction and maintenance of asphalt pavements

The increasing use of recycled materials in asphalt pavements calls for environmental assessment of such impacts as the energy input and CO₂ footprint. Life cycle assessment (LCA) is being accepted by the road industry for such purpose. It aims to quantify and collate all the environmental impacts from the life time of the product or process. This paper reviews relevant LCA resources worldwide, identifies the knowledge gap for the road industry, and describes the development of an LCA model for pavement construction and maintenance that accommodates recycling and up-to-date research findings. Details are provided of both the methodology and data acquisition. This is followed by a discussion of the challenges of applying LCA to the pavement construction practice, and recommendations for further work. In the case study, the model is applied to an asphalt paving project at London Heathrow Terminal-5 (LHR), in which natural aggregates were replaced with waste glass, incinerator bottom ash (IBA) and recycled asphalt pavements (RAP). Production of hot mix asphalt and bitumen was found to represent the energy intensive processes. This is followed by data analysis and sensitivity check. Further development of the model includes expanding the database to accommodate the recycling and maintenance practice in the UK, and taking into account the effect that roadwork has on traffic emissions. The LCA model can be further tested and calibrated as a decision support tool for sustainable construction in the road industry.     

化工资源回收利用与废水综合治理

武汉市某化工厂生产废水毒性大、污染物浓度高、盐度高、可生化性差,传统的工业废水处理工艺难以实现达标治理。本着循环经济的发展思路,通过废水现场调研和物料衡算,分析废水中的可资源化利用物质,对废水进行清污分流和污染物(DMF)资源化利用。经济分析表明,资源回收利用与污水综合治理相结合的方案不但可以实现废水的达标排放,还可以产生一定的经济效益。     

浅谈循环经济立法及再生资源产业化发展

论述了循环经济法制化发展的重要意义.以再生水为例,指出我国再生资源产业化发展潜力巨大,大力发展再生资源产业,对发展我国循环经济,建设循环型社会具有重要意义.     

Ban on landfilling of wooden pallets in North Carolina: an assessment of recycling and industry capacity

Pallets literally move the world and an estimated 2 billion of them are in use in the U.S. every day. However, pallets have a short life span and thus consume vast quantities of resources. They are also responsible for 2–3% of all waste landfilled in the United States. This is despite the fact that technologies and markets exist that allow pallets to be reused, recycled, converted into other products or turned into mulch, boiler fuels or alcohols (ethanol). The State of North Carolina's legislature debated a ban on landfilling pallets for several years and has now enacted legislation to ban this practice beginning in 2009. This study provided information used to help reach that decision.North Carolina had 103 known pallet recycling operations that were surveyed in 2003–2004. Using 34 responses, the total pallet recycling capacity in North Carolina was close to 60 million units per year, while 34 million pallets were actually recycled in 2003. The average operation employed nearly 34 persons and recycled about 326,000 pallets per year. On average, 20% of the pallets received by a recycling operation were reused, 45% were refurbished, 19% were recycled, and 15% were ground. The industry generally thought that a ban on landfilling pallets was a good idea (56%) with 18% indicating it was a bad idea. Another 18% of respondents did not care and 9% had different ideas.     

The effect of coupling coagulation and flocculation with membrane filtration in water treatment： A review

Water supply and sanitation demands are foreseen to face enormous challenges over the coming decades to meet the fast growing needs in a global perspective. Significant growth in the industry is predicted and membrane separation technologies have been identified as one of the possible solutions to meet future demands. Application and implementation of membrane technology is expected both in production of potable water as well as in treatment of wastewater. In potable water production membranes are substituting conventional separation technologies due the superior performance, potential for less chemical use and sludge production, as well as the potential to fulfill hygienic barrier requirements. Membrane Bio-Reactor (MBR) technology is probably the membrane process which has had most success and has the best prospects for the future in wastewater treatment. Trends and developments indicate that this technology is becoming accepted and is rapidly becoming the best available technology (BAT) for many wastewater treatment applications. A major drawback of MBR systems is membrane fouling. Studies have shown that fouling mitigation in MBR systems can potentially be done by coupling coagulation and flocculation to the process.     

小麦燃料乙醇循环产业生态足迹分析

为提高循环产业研究结果的可比性,以小麦燃料乙醇生产为例,采用生态足迹方法对各子系统的生态占用、资源循环利用和污染排放等进行分析.小麦燃料乙醇循环产业包括农业生产、乙醇生产、循环生产和废物处理4个子系统.结果表明:小麦燃料乙醇循环产业链的延长将增加生态足迹,其中农业生产子系统生态足迹占系统生态足迹的比例最大,主要是因为该子系统中耕地占用较大;生态足迹的经济效益随产业链的延长而增加,说明延长产业链可以提高资源利用效率;循环生产和废物处理子系统解决了乙醇生产过程中环境污染问题;系统的能源足迹和水足迹占用比例较大,应考虑降低能耗和水耗.结果也表明,生态足迹评价方法能够全面反映循环产业各子系统资源利用和环境污染状况,是评价循环产业系统的有效手段.      

荧光原位杂交技术解析发酵产氢细菌群落结构

应用荧光原位杂交(FISH)技术,研究了连续流搅拌槽式(CSTR)发酵制氢反应器中2种产氢发酵类型的菌群组成和发酵类型转化过程中的菌群种类和数量变化及其对产氢速率、生物量和发酵产物的影响.结果表明,梭菌属和肠杆菌科在决定产氢发酵类型方面有重要作用.以梭菌为优势种群的乙醇型发酵比以肠杆菌为优势种群的丁酸型发酵具有更佳的产氢能力.实验结果能够与生物发酵系统常规监测指标形成很好的印证.     

餐饮废物制取燃料乙醇发酵条件研究

通过单因素试验选取试验因子,并根据Box-Benhnken的中心组合试验设计原理,在单因素试验基础上采用四因素三水平响应面分析法,以乙醇含量为响应值,对发酵条件进行优化.结果表明,发酵温度、发酵时间、初始pH和接种量与乙醇含量存在显著相关性.最佳发酵条件为发酵温度33.8℃、发酵时间101.5h、初始pH=4.6、接种量16.6%.通过实验室小试,在最优发酵条件下,乙醇含量可达到6.93%,乙醇发酵效果较好.还原糖利用率达到88.7%,每吨干物质原料可产192.8L乙醇.